ABSTRACT:

                        The determination of sensitizing centers and band gap of the photoconductive materials

    In this study, Selenium(Se) photoconductor was developed by mixing the power Se with the powder of Chlorine (Cl) under the conditions of high vacuum and high temperature. The production of ZnS photoconductor was also acoomplished from the mixture of ZnS and ZnCl powders under the same conditions. It was found that the developed Se and ZnS photoconductors were very sensitive to the light. The density of sensitizing centers in these photoconductors were determined by using Capacitance-Voltage (C-V) and Space-Charge-Limited methods. the energy value of band gap of Se and ZnS and the energy levels of sensitizing centers in the forbidden gap of Se and ZnS were evaluated by variation of photoconductivity excitation with wavelength method.
    The density of sensitizing centers was found to chanege linearity with the light intensity; the energy value of band gap of Se and ZnS photoconductors were found to be in good agreement with theoretical values.

KEYWORDS:    recombination Centers II, Sensitizing centers, Photoconductivity, Se, ZnS.